Detailed Description

This interface represents a light source in world space. The light's position and direction cannot be specified directly; instead, a separate ILightTransform node must be used that references the ILight node it is supposed to move/rotate.

By default, the light source's direction runs along the negative Z axis, i.e. parallel to the default camera viewing direction. The default position is (0/0/0). Depending on the actual type of this light source, either the light's position, direction, or both are used for lighting calculations:

DIRECTIONAL: Only direction is used. The light's position is ignored, resulting in parallel light rays, like a light source inifinitely far away.

POINT: Only position is used, with light rays emitted in all directions from that point.

SPOT: Light rays are emitted from the given point, in the given direction.

When using directional or point lights for rendering into a shadow map, this method (together with any of the SetFieldOfView methods below) can be used to define the actual volume considered for generating the shadow map.

This method sets the radius of the light's bounding sphere, which is used to determine the nearest light source within a group, for every geometry object for which the respective group is active. For rendering projected light textures, this also represents the far plane of the light projection matrix.